The production of 3D video is to a large extent determined by the targeted viewing conditions, e.g. cinema projection in a theatre or display on a domestic 3D-TV display. The main parameters that are taken into account during production are is the width of the targeted screen and the distance between the viewer and the screen.
When 3D video content designed for specific viewing conditions shall be displayed under different viewing conditions, the 3D video content should be modified to fit these new viewing conditions. Otherwise the 3D experience quality may be rather low due to shallow 3D effects or discomfort and visual fatigue. Despite this problem, today generally no kind of adaptation is performed. This sometimes leads to very poor 3D effects, e.g. when playing 3D movies excerpts or trailers on a 3D-TV display.
With the current growth of the 3D Cinema market the adaptation of 3D video content will become an important issue for the replication and distribution of 3D-DVD (Digital Versatile Disc) and 3D-BD (BluRay Disc). The goal is to avoid the need to handle several masters for the same 3D video content.
Today the most primarily investigated approach for adaptation of 3D video content consists in synthesizing new “virtual” views located at the ideal camera positions for the targeted viewing conditions. This view synthesis enables pleasing 3D effects without altering the structure of the scene shot. However, view synthesis is complex and expensive in terms of computations. It requires the delivery of high quality disparity maps along with color video views, as the use of poor quality disparity maps induces unacceptable artifacts in the synthesized views. Though for computer-generated content the generation of the required disparity maps is rather easy, for natural video contents this is a rather challenging task. Up to now no reliable chain from disparity estimation to view synthesis is available.
Even if improved solutions for disparity estimation become available, it still remains desirable to provide a reasonable, low-complex adaptation solution, e.g. for 3D set-top boxes.